Comparative pharmacokinetic and bioavailability studies of three salvianolic acids after the administration of Salviae miltiorrhizae alone or with synthetical borneol in rats

Effect and pharmacological mechanism of Salvia miltiorrhiza and its characteristic extracts on diabetic nephropathy

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic nephropathy (DN) is a severe diabetic microvascular complication with an increasing prevalence rate and lack of effective treatment. Traditional Chinese medicine has been proven to have favorable efficacy on DN, especially Salvia miltiorrhiza Bunge (SM), one of the most critical and conventional herbs in the treatment. Over the past decades, studies have demonstrated that SM is a potential treatment for DN, and the exploration of the underlying mechanism has also received much attention.

AIM OF THIS REVIEW

This review aims to systematically study the efficacy and pharmacological mechanism of SM in the treatment of DN to understand its therapeutic potential more comprehensively.

MATERIALS AND METHODS

Relevant information was sourced from Google Scholar, PubMed, Web of Science, and CNKI databases.

RESULTS

Several clinical trials and systematic reviews have indicated that SM has definite benefits on the kidneys of diabetic patients. And many laboratory studies have further revealed that SM and its characteristic extracts, mainly including salvianolic acids and tanshinones, can exhibit pharmacological activity against DN by the regulation of metabolism, renal hemodynamic, oxidative stress, inflammation, fibrosis, autophagy, et cetera, and several involved signaling pathways, thereby preventing various renal cells from abnormal changes in DN, including endothelial cells, podocytes, epithelial cells, and mesangial cells.

CONCLUSION

As a potential drug for the treatment of DN, SM has multi-component, multi-target, and multi-pathway pharmacological effects. This work will not only verify the satisfactory curative effect of SM in the treatment of DN but also provide helpful insights for the development of new anti-DN drugs and the application of traditional Chinese medicine.

Natural borneol serves as an adjuvant agent to promote the cellular uptake of piperlongumine for improving its antiglioma efficacy

Piperlongumine (PL) can selectively inhibit the proliferation of various cancer cells by increasing reactive oxygen species (ROS) level to cause a redox imbalance in cancer cells rather than in normal cells. However, the clinical application of PL is limited by its poor cellular uptake. Natural borneol (NB) is extracted from the fresh branches and leaves of Cinnamomum camphora (L.) Presl. with the purity of (+)-borneol no less than 96.0%. NB has been often used as an adjuvant agent to promote the cellular uptake of other drugs. This study aims to investigate the effect of NB on the cellular uptake of PL for improving its antiglioma efficacy and underlying mechanism. NB obviously promoted the cellular uptake of PL with a 1.3-fold increase in the maximum peak concentration and an earlier peak time of 30 min in C6 glioma cells. The cellular uptake of PL was enhanced by NB through down-regulating the expression levels of P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2). The combination of NB and PL significantly induced higher levels of ROS, which increased apoptosis and enhanced G2/M cycle arrest of C6 glioma cells, compared to PL alone administration. NB-enhanced antiglioma efficacy of PL without side effects was confirmed in tumor-bearing mice, which was attributed to the improved cellular uptake of PL. The distribution of PL in the tumor tissue of combined group increased 2.39 times than that of PL-treated group. We firstly report NB as an adjuvant agent to improve the antiglioma efficacy of PL in a ROS-dependent manner, which is due to the enhanced cellular uptake of PL by NB though down-regulating the expression levels of ABCB1 and ABCG2. This work provides a new strategy to promote the cellular uptake of PL with great potential for the treatment of glioma.

The history, stereochemistry, ethnopharmacology and quality assessment of borneol

ETHNOPHARMACOLOGICAL RELEVANCE

Borneol (BO) represents a global trade-driven spreading of ethnic medicine traceable to the classical age, and won its name specific to its original habitat "Borneo". BO shows broad spectral pharmacological effects, such as anti-inflammatory, analgesic, antipyretic, inducing resuscitation, and widely applied in the protection and treatment of cardiovascular and cerebrovascular diseases, used singly or mostly in compound formulae.

AIM OF THE STUDY

Three stereoscopic configuration forms of BO, l-borneol (LB), d-borneol (DB), and dl-borneol (synthetic, SB), are formulated in broad spectral application, yet their diverse pharmacodynamic and pharmacokinetic properties caused by configurations, and accurate assay and quality assessment are often overlooked. A systematic review and analysis of lumped studies and applications is necessary to clarify the relationship between configuration and its original plant, analysis method, activity and side effect BO in order to guarantee the efficacy and safety during their application.

MATERIALS AND METHODS

The public databases including PubMed, Web of Science, Google Scholar, China National Knowledge Infrastructure were referenced to summarize a comprehensive research and application data of BO published up to date.

RESULTS

This review includes following sections: History and current status, Stereochemistry, Ethnopharmacology, and Quality assessment. In the section of history, the changes of the plant origins of the two isomeric forms of natural BO were described respectively, and the methods for synthetic racemate SB were also included. The section of stereochemistry deals with the stereoscopic structures, physical/chemical property, optical rotation of the three forms of BO, as well as the main related substances like isoborneol, obtained in SB via chemical transformation of camphor and turpentine oil. In the section of Ethnopharmacology, pharmacological activities and pharmacokinetics of different forms of BO were discussed. BO is usually used as an "adjuvant", by enhancing the permeability of the blood-brain barrier and intervene the ADME/T pathways of the other ingredients in the same formulation. In the section of quality assessment, the analytical methods, including chromatography, especially GC, and spectroscopy were addressed on the chiral separation of the coexisting enantiomers.

CONCLUSIONS

This overview systematically summarized three forms of BO in terms of history, stereochemistry, ethnopharmacology, and quality assessment, which, hopefully, can provide valuable information and strategy for more reasonable application and development of the globally reputed ethnic medicine borneol with characteristics in stereochemistry.

Salvia miltiorrhiza Bge. (Danshen) in the Treating Non-alcoholic Fatty Liver Disease Based on the Regulator of Metabolic Targets

Non-alcoholic fatty liver disease (NAFLD) is rapidly prevalent due to its strong association with increased metabolic syndrome such as cardio- and cerebrovascular disorders and diabetes. Few drugs can meet the growing disease burden of NAFLD. Salvia miltiorrhiza Bge. (Danshen) have been used for over 2,000 years in clinical trials to treat NAFLD and metabolic syndrome disease without clarified defined mechanisms. Metabolic targets restored metabolic homeostasis in patients with NAFLD and improved steatosis by reducing the delivery of metabolic substrates to liver as a promising way. Here we systematic review evidence showing that Danshen against NAFLD through diverse and crossing mechanisms based on metabolic targets. A synopsis of the phytochemistry and pharmacokinetic of Danshen and the mechanisms of metabolic targets regulating the progression of NAFLD is initially provided, followed by the pharmacological activity of Danshen in the management NAFLD. And then, the possible mechanisms of Danshen in the management of NAFLD based on metabolic targets are elucidated. Specifically, the metabolic targets c-Jun N-terminal kinases (JNK), sterol regulatory element-binding protein-1c (SREBP-1c), nuclear translocation carbohydrate response element–binding protein (ChREBP) related with lipid metabolism pathway, and peroxisome proliferator-activated receptors (PPARs), cytochrome P450 (CYP) and the others associated with pleiotropic metabolism will be discussed. Finally, providing a critical assessment of the preclinic and clinic model and the molecular mechanism in NAFLD.

Borneol enhances the protective effect against cerebral ischemia/reperfusion injury by promoting the access of astragaloside IV and the components of Panax notoginseng saponins into the brain

BACKGROUND

Astragalus and Panax notoginseng are significant traditional Chinese medicines for treating ischemic stroke, with astragaloside IV (AST IV) and Panax notoginseng saponins (PNS) being the major effective compounds, respectively. These compounds can also be used in combination. We have previously shown that AST IV and PNS have an antagonistic effect on cerebral ischemia/reperfusion (I/R) injury, and the combination of these two drugs can elevate this effect; unfortunately, AST IV and PNS cannot easily enter the brain tissues through the blood brain barrier (BBB). Previous studies have confirmed that the combination of borneol with other agents could promote the penetration of the drug components through the BBB. However, it remains unclear whether borneol can promote entry of the active components of AST IV and PNS into the brain tissues and enhance their effect against cerebral ischemia.

OBJECTIVE

This study aimed to investigate the effects of a combination of borneol with AST IV and PNS against I/R injury and explore the mechanisms of borneol-promoting penetration of drug components into the BBB based on the drug transport of brain tissues.

METHODS

A rat model of focal cerebral I/R injury was established, and drugs, including borneol, AST IV, and PNS, as well as their combinations were intragastrically administered. Subsequently, drug efficacy was assessed, and the condition of AST IV and PNS active components (Rg1, Rb1, R1) delivered into the brain was analyzed. Moreover, BBB permeability was determined, and the expression of related drug transporters and their genes were evaluated.

RESULTS

After treatment with borneol, AST IV, PNS, AST Ⅳ+PNS, and borneol+AST Ⅳ+PNS after cerebral I/R, the neurological function deficit scores, cerebral infarct rate, and brain water content markedly decreased. The effects of the three-drug-combination were better than those of the drugs used alone and those of AST Ⅳ+PNS. Moreover, after I/R in rats, AST IV and the components of PNS (Rg1, Rb1, R1) were mainly found in the cerebral cortex and in the cerebellum, respectively, when used alone. Borneol combined with AST IV and PNS increased the contents of AST IV, Rb1, Rg1, and R1 in the cerebral cortex and in the cerebellum, thus, promoting the enrichment of active components to the cerebral cortex, especially to the affected side. In addition, following I/R, diffuse distribution of lanthanum particles in the basement membrane, intercellular and intracellular locations of rat brain tissues indicated BBB destruction and increase in permeability, which were alleviated in each drug group. The effects of borneol combined with AST IV and PNS were stronger than those of the drug single-used and those of the AST IV+PNS group. Finally, the expression of effluent transporters (ET) and their genes, including P-glycoprotein (P-gp), multidrug resistance protein (MRP)-1, MRP-2, MRP-4, and MRP-5 in brain tissues, strikingly increased after I/R. Borneol remarkedly down-regulated the protein expression of P-gp, MRP-2, and MRP-4 in the brain, whereas PNS down-regulated MRP-4 and MRP-5 protein expression. AST IV, AST IV+PNS, and bornoel+AST IV+PNS effectively decreased the expression of P-gp, MRP-2, MRP-4, and MRP-5 proteins. The effects of the three-drug combination were significantly greater than those of the drug single-used and AST IV+PNS groups. The expression of each ET gene manifested corresponding results. Meanwhile, PNS, AST IV+PNS, and bornoel+AST IV+PNS significantly inhibited the down-regulation of the uptake transporter organic anion transporting polypeptide (OATP)-2 expression, and the effect of bornoel+AST IV+PNS was stronger than that of other groups.

CONCLUSION

After I/R, the brain tissues were injured, BBB permeability increased, expression of critical ET and their genes were markedly up-regulated, and the main uptake transporters were down-regulated. We propose that the combination of borneol, AST IV and PNS could enhance the effect against cerebral I/R injury and protect BBB integrity. The potential mechanism might be the delivery of AST IV and active components of PNS to the brain tissues after treatment in combination with borneol, which could be effectively promoted by down-regulating the expression of ETs and up-regulating the expression of uptake transporters in the brain tissues. This study was the first to demonstrate that borneol combined with AST IV+PNS enhanced the effect against cerebral I/R injury through promoting the entry of AST and PNS active components to the brain tissues. Thus, this study proposes an instructive role in developing effective active ingredients combination of Chinese medicine with clear ingredients and synergistic effects in terms of the characteristic of borneol.

The effects of borneol on the pharmacokinetics and brain distribution of tanshinone IIA, salvianolic acid B and ginsenoside Rg1 in Fufang Danshen preparation in rats

Fufang Danshen preparation (FDP) is consisted of Salviae Miltiorrhizar Radix et Rhizoma (Danshen), Notoginseng Radix et Rhizoma (Sanqi) and Borneolum Syntheticum (borneol). FDP is usually used to treat myocardial ischemia hypoxia, cerebral ischemia and alzheimer's disease, etc. In the treatment of cerebrovascular diseases, borneol is usually used to promote the absorption and distribution of the bioactive components to proper organs, especially to the brain. The purpose of this study is investigating the effects of borneol on the pharmacokinetics and brain distribution of tanshinone IIA (TS IIA), salvianolic acid B (SAB) and ginsenoside Rg1 in FDP. Male healthy Sprague-Dawley (SD) rats were given Danshen extracts, Sanqi extracts (Panax notoginsengsaponins) or simultaneously administered Danshenextracts, Sanqi extracts and borneol. Plasma and brain samples were collected at different points in time. The concentration of TS IIA, SAB and Rg1 was determined by UPLC-MS/MS method. The main pharmacokinetics parameters of plasma and brain tissue were calculated by using Phoenix WinNolin 6.1 software. In comparison with Danshen and Sanqi alone, there were significant differences in pharmacokinetic parameters of TS IIA, SAB and Rg1, and the brain distribution of SAB and TS IIA when Danshen, Sanqi and borneol were administrated together. Borneol statistically significant shortened t_max of TS IIA, SAB and Rg1 in plasma and brain, increased the bioavaiability of Rg1, inhibited metabolism of Rg1 and enhanced the transport of TS IIA and SAB to brain. These results indicated that borneol could affect the multiple targets components and produce synergistic effects. Through accelerating the intestinal absorption and brain distribution, borneol caused the effective ingredients of Danshen and Sanqi to play a quicker therapeutic role and improved the therapeutic effect.

Effects of Borneol on the Release of Compound Danshen Colon-Specific Osmotic Pump Capsule In Vitro and Pharmacokinetics Study in Beagle Dogs

Borneol can enhance the bioavailability of several other drugs by opening the blood-brain barrier and inhibiting P-glycoprotein (P-gp) efflux. However, whether borneol will impact the bioavailability and the mechanism of compound Danshen colon-specific osmotic pump capsule (CDCOPC) remains unclear. This study aimed to determine the effects of borneol on the in vitro release and in vivo pharmacokinetic characteristics of CDCOPC. Besides, the in vitro release behavior of CDCOPC was further assessed by chromatographic fingerprints. The in vitro release studies showed that borneol followed the zero-order release and hardly impacted the in vitro release of Salvia miltiorrhiza and Panax notoginseng in CDCOPC. Moreover, as revealed from the similarity results of fingerprints, the in vitro release of different components of CDCOPC was almost simultaneous. Compared with the commercially available tablets, the pharmacokinetics studies suggested that both CDCOPCs containing and lacking borneol could significantly prolong the retention time of these effective components; their average relative bioavailability values increased to 448.70% and 350.97%, respectively. Notably, borneol significantly improved the relative bioavailability of some components of CDCOPC, such as salvianolic acid B (SAB), tanshinone IIA (Tan IIA), notoginsenoside R₁ (R₁), ginsenoside Rg₁ (Rg₁), and ginsenoside Re (Re) from CDCOPC, while it slightly impacted ginsenoside Rb₁ (Rb₁) and ginsenoside Rd (Rd). Summarily, borneol is capable of improving the bioavailability of some effective components in CDCOPC, which is critical to design with CDCOPC for enhanced bioavailability. This study could also help reveal the composition principle of the compound Danshen formula (CDF).

Possible applications of salvianolic acid B against different cancers

Cancer is the second death causing disease worldwide after cardiovascular abnormalities. The difficulty in treating tumor cells with more precise targeted interventions and recurrence of cancer after treatment may pose great difficulty in developing sustainable therapeutic regimens. These limitations have prompted the need to explore several compounds with ability to cease tumor growth while at the same time induce apoptosis of tumor cells. Several studies have emphasized the use of natural compounds as antitumor agents due to their high efficacy against cancer cells and low toxicity in normal cells. Salvianolic acid B (SAB), a naturally occurring phenolic compound extracted from the radix of Chinese herb Salvia miltiorrhiza can induce apoptosis in different types of tumor cells. It can be used to treat cardiovascular and neurodegenerative disorders, hepatic fibrosis, and cancers. Several studies have shown that SAB can mitigate tumorigenesis by modulating MAPK, PI3K/AKT, and NF-ĸB signaling pathways. It also sensitizes the tumor cells to different anti-cancer agents by reversing the multi-drug resistance mechanisms found in tumor cells. This review summarizes the studies showing antitumor potential of SAB in different types of cancer cell lines, animal models and highlights the possible mechanisms through which SAB can induce apoptosis, inhibit growth and metastasis in tumor cells. Moreover, the possible role of nano-technological approaches to induce targeted delivery of SAB to eradicate tumor cells has been also discussed.

AMPK in microvascular complications of diabetes and the beneficial effects of AMPK activators from plants

BACKGROUND

Diabetes mellitus is a multifactorial disorder with the risk of micro- and macro-vascular complications. High glucose-induced derangements in metabolic pathways are primarily associated with the initiation and progression of secondary complications namely, diabetic nephropathy, neuropathy, and retinopathy. Adenosine monophosphate-activated protein kinase (AMPK) has emerged as an attractive therapeutic target to treat various metabolic disorders including diabetes mellitus. It is a master metabolic regulator that helps in maintaining cellular energy homeostasis by promoting ATP-generating catabolic pathways and inhibiting ATP-consuming anabolic pathways. Numerous pharmacological and plant-derived bioactive compounds that increase AMP-activated protein kinase activation has shown beneficial effects by mitigating secondary complications namely retinopathy, nephropathy, and neuropathy.

PURPOSE

The purpose of this review is to highlight current knowledge on the role of AMPK and its activators from plant origin in diabetic microvascular complications.

METHODS

Search engines such as Google Scholar, PubMed, Science Direct and Web of Science are used to extract papers using relevant key words. Papers mainly focusing on the role of AMPK and AMPK activators from plant origin in diabetic nephropathy, retinopathy, and neuropathy was chosen to be highlighted.

RESULTS

According to results, decrease in AMPK activation during diabetes play a causative role in the pathogenesis of diabetic microvascular complications. Some of the plant-derived bioactive compounds were beneficial in restoring AMPK activity and ameliorating diabetic microvascular complications.

CONCLUSION

AMPK activators from plant origin are beneficial in mitigating diabetic microvascular complications. These pieces of evidence will be helpful in the development of AMPK-centric therapies to mitigate diabetic microvascular complications.

Pharmacokinetic studies of multi-bioactive components in rat plasma after oral administration of Xintiantai Ⅰ extract and effects of guide drug borneol on pharmacokinetics

Objective

To investigate the in vivo pharmacokinetic characteristics of 17 bioactive components including ginsenoside Rg1, Rb1, Rd, berberine, epiberberine, jatrorrhizine, palmatine, columbamine, coptisine, evodiamine, dehydroevodiamine, rutaecarpine, limonin, hyperin, curcumin, demethoxycurcumin and bisdemethoxycurcumin in rat plasma after oral administration of Xintiantai I extract powder (XI) and Xintiantai I without guide drug borneol extract powder (XI without borneol), and study the compatibility effects of guide drug borneol on the pharmacokinetics.

Methods

A UHPLC-MS/MS method was established and fully validated for the comparative pharmacokinetics of 17 bioactive components. The pharmacokinetics parameters of 17 bioactive components after oral administration of XI and XI without borneol were calculated by the software of DAS 3.0 and intercompared.

Results

The specificity, linearity, lower limit of quantification (LLOQ), precision, accuracy, extraction recovery rates, matrix effects, and stability of the UHPLC-MS/MS assay were good within the acceptance criteria from FDA guidelines. Guide drug borneol can significantly increase AUC of G-Rd, palmatine, hyperin, curcumin, demethoxycurcumin, bisdemethoxycurcumin and C_max of 16 bioactive components except for dehydroevodiamine (P < 0.05), decrease T_max of G-Rd, berberine, columbamin, coptisine, limonin and MRT of 17 bioactive components in XI group (P < 0.05).

Conclusion

Guide drug borneol enhanced the absorption of G-Rd, palmatine, hyperin, curcumin, demethoxycurcumin and bisdemethoxycurcumin.

Influence of Orally Administered Borneol on the Expression of Hepatic Transporters in Rats

BACKGROUND AND OBJECTIVE

Borneol, a traditional Chinese medicine (TCM), is often orally co-administered with other TCM and chemical drugs, but the drug-drug interactions between borneol and the other compounds remains unclear. This work investigates the effect of orally administered borneol on the transcription and expression of hepatic uptake transporters (Ntcp, Oatp2b1, Oatp1a1, Oatp1a4, Oct1, Oct2, Octn2 and Oat2) and efflux transporters (Mdrla, Mrp2, Mrp4 and Mrp5) in rats, aiming to obtain essential information to guide its clinical applications.

METHODS

Rats were administered borneol (33, 100 and 300 mg/kg/day, respectively) and vehicle (control) orally via intragastric gavage for 7 consecutive days. The mRNA levels of rat hepatic uptake transporters (Ntcp, Oatp2b1, Oatp1a1, Oatp1a4, Oct1, Oct2, Octn2 and Oat2) and efflux transporters (Mdrla, Mrp2, Mrp4 and Mrp5) were determined using real-time quantitative PCR, while the hepatic Ntcp, Mdrla, Mrp2, Mrp4 and Mrp5 proteins were quantified using western blotting.

RESULTS

The oral administration of borneol led to dose-dependent inhibition of mRNA and protein expression of Mrp4 and Mdr1a, dose-independent inhibition of mRNA and protein expression of Mrp2, and inverse dose-dependent inhibition of mRNA and protein expression of Ntcp. No significant effects were observed for mRNA expression of the other transporters tested following borneol administration.

CONCLUSIONS

Oral administration of borneol may affect the metabolism of substances that are involved in bile acid enterohepatic circulation and substrates of Ntcp, Mdrla, Mrp2 and Mrp4 transporters.

Influence Factors of the Pharmacokinetics of Herbal Resourced Compounds in Clinical Practice

Herbal medicines have been used to prevent and cure diseases in eastern countries for thousands of years. In recent decades, these phytotherapies are becoming more and more popular in the West. As being nature-derived is the essential attribute of herbal medicines, people believe that taking them for diseases treatment is safe enough and has no side-effects. However, the efficacy of herbal resourced compounds (HRC) depends on the multiple constituents absorbed in the body and their pharmacokinetics. Thus, many factors will influence the clinical practice of HRC, i.e., their absorption, distribution, metabolism, and excretion (ADME). Among these factors, herb-drug interaction has been widely discussed, as these compounds may share the same drug-metabolizing enzymes and drug transporters. Meanwhile there are many other potential factors that can also change the ADME of HRC, including herb pretreatment, herb-herb interactions, pathological status, gender, age of patient, and chemical and physical modification of certain ingredients. With the aim of ensuring the efficacy of HRC and minimizing their clinical risks, this review provides and discusses the influence factors and artificial improvement of the pharmacokinetics of HRC.

Some pharmacokinetic parameters of salvianolic acid A following single-dose oral administration to rats

CONTEXT

Salvianolic acid A (Sal A) is a hydrophilic bioactive compound isolated from Salvia miltiorrhiza Bunge (Lamiaceae). It exerts beneficial effects after oral administration on diabetic complications.

OBJECTIVE

To systematically study the absorption, distribution and excretion of Sal A after single-dose oral administration.

MATERIALS AND METHODS

Animal experiments were conducted in Sprague-Dawley rats. Plasma was sampled at designated times after oral doses of 5, 10 and 20 mg/kg, and an intravenous dose of 50 μg/kg. Tissues were harvested at 10, 60 and 120 min postdosing. Bile, urine and feces were collected at specified intervals before and after dosing. Absorption and distribution characteristics were analyzed by LC-MS, and excretion characteristics were analyzed by UPLC-MS/MS. The Caco-2 cell model was applied to investigate potential mechanisms.

RESULTS

The C_max (5 mg/kg: 31.53 μg/L; 10 mg/kg: 57.39 μg/L; 20 mg/kg: 111.91 μg/L) of Sal A increased linearly with doses (r> 0.99). The calculated absolute bioavailability was 0.39-0.52%. Transport experiment showed poor permeability and the ratio of P_B-A to P_A-B was 3.13-3.97. The highest concentration of Sal A was achieved in stomach followed by small intestine and liver, and it could also be detected in brain homogenate. Approximately 0.775% of its administered dose was excreted via feces, followed by bile (0.00373%) and urine (0.00252%).

DISCUSSION AND CONCLUSIONS

These results support the future development of Sal A as an oral drug for the treatment of diabetic complications. Future research should be conducted to investigate the reason for its poor bioavailability and improve this situation.

Enhancing both oral bioavailability and brain penetration of puerarin using borneol in combination with preparation technologies

Now there are few good oral preparations of puerarin used in cerebrovascular diseases because of its poor oral absorption caused by the low water solubility and the poor penetration into brain. In this study, three oral formulations of puerarin, nanocrystals suspension (NCS), inclusion compounds solution (ICS) and self-microemulsifying drug delivery system (SMEDDS) were prepared with borneol as an oral brain-targeting enhancer. A rat syngeneic in vitro model of the brain-blood barrier (BBB) was established to investigate effects of borneol on the permeability of puerarin across the BBB. The pharmacokinetics of puerarin in mice after oral administration was investigated by a high performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) method. The in vitro BBB model study showed the permeability of puerarin was increased significantly (p < 0.05) and the value of transepithelial electrical resistance at 2 h was decreased significantly (p < 0.01) when the concentration of borneol was over 12.5 μg/mL compared with the control group. The pharmacokinetics results indicated borneol with doses of over 50 mg/kg could obviously increase both intestinal absorption and brain penetration of puerarin. With co-administration of borneol (100 mg/kg), the AUC of puerarin both in plasma (AUCplasma) and in brain (AUCbrain) for SMEDDS were significantly higher than those for NCS (p < 0.01) and ICS (p < 0.05). These results suggested borneol in combination with SMEDDS could improve both the oral absorption and the brain penetration of puerarin in mice, which was promising for the development of an oral formulation of puerarin used in cerebrovascular diseases.

Effect of compatible herbs on the pharmacokinetics of effective components of Panax notoginseng in Fufang Xueshuantong Capsule

Fufang Xueshuantong (FXT) is a well-known Chinese herbal formula which has been used to treat cardiovascular and ophthalmic diseases, especially diabetic retinopathy. Panax notoginseng (Burkill) F.H. Chen (PN) is the main herb of FXT, whose major bioactive constituents are ginsenosides. However, the scientific basis of the compatibility of FXT is still ambiguous. The present study investigated the scientific basis of the compatibility of FXT by comparing the pharmacokinetics of marker compounds after oral administrations of PN and FXT. A high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method was developed for simultaneous detection of notoginsenoside R1 (NR1), ginsenoside Rg1 (GRg1), and ginsenoside Rb1 (GRb1) in rat plasma. The pharmacokinetic studies of FXT and PN were performed using the established method with the pharmacokinetic parameters being determined by non-compartmental analysis. The results showed that the pharmacokinetic parameters (maximum concentration, area under the curve (AUC_0-t), clearance, and mean residence time) of NR1, GRg1, and GRb1 were significantly different after oral administration of FXT (P<0.05) compared with PN. The AUC_0-t values of GRg1 and GRb1 were 1.7- and 3.4-fold greater, respectively, in FXT than in PN. The compatible herbs of FXT could prolong the retention time and increase the systemic exposure of NR1, GRg1, and GRb1 compared with PN in vivo, providing some scientific basis for the compatibility and clinical use of FXT.

Therapeutic and nutraceutical potential of rosmarinic acid-Cytoprotective properties and pharmacokinetic profile

Rosmarinic acid (RA) is a natural polyphenolic antioxidant derived from many common herbal plants. This compound displays several important biological properties, including anti-inflammatory, antiviral, antibacterial, antidepressant, anticarcionogenic, and chemopreventive properties. The importance of its activities and its possible application in processed foods as a natural antioxidant has reached a new interest levels in recent years. The health effects of this polyphenol depend greatly on both its intakes and bioavailability. This review focuses on the importance of RA as a dietary supplement, and summarizes its pharmacokinetics and metabolism, including the factors that limit its oral bioavailability which leads to a lower therapeutic action. Further experimental investigations are needed to optimize and enhance the oral bioavailability of this natural compound which consequently will help increasing therapeutic efficacy of RA in vivo.

Different effects of (+)‑borneol and (‑)‑borneol on the pharmacokinetics of osthole in rats following oral administration

Osthole is the primary active component of a number of herbal plants such as the Cnidium monnieri fruit. In traditional Chinese herb medicine, osthole is commonly used in combination with borneol to obtain improved pharmacological effects. The aim of the present study was to investigate the effect of borneol enantiomers on the pharmacokinetics of osthole. An appropriate high‑performance liquid chromatography (HPLC) method was applied to determine the concentrations of osthole in plasma. Following oral administration of osthole alone or combined with borneol in rats, blood samples were collected and analyzed by HPLC. The results demonstrated that there were statistically significant differences in the pharmacokinetic parameters of osthole between osthole administration alone and co‑administration with borneol. When combined with synthetic borneol, the AUC0‑t, AUC0‑∞ and Cmax of osthole increased by 48.153, 104.708 and 92.630%, respectively, while the CL/F decreased by 51.251%. When combined with (+)‑borneol, the AUC0‑t, AUC0‑∞ and Cmax of osthole were increased by 61.561, 78.167, and 51.769%, respectively, while the CL/F decreased by 44.174% (P<0.01). In addition, when combined with (‑)‑borneol, the AUC0‑t, AUC0‑∞ and Cmax of osthole increased by 115.856, 167.786 and 271.289%, respectively, while the CL/F decreased by 60.686% (P<0.01). These results indicated that borneol may enhance gastrointestinal absorption and inhibit the metabolism of osthole. In addition, the promotional effect of (‑)‑borneol on the pharmacokinetic parameters of osthole was greater than that of (+)‑borneol.

Pharmacokinetics of rosmarinic acid in rats by LC-MS/MS: absolute bioavailability and dose proportionality

The pharmacokinetic properties of RA were characterized as rapid absorption, middle-speed elimination, poor absolute bioavailability, and lack of dose proportionality.

Rosmarinic acid ameliorates hyperglycemia and insulin sensitivity in diabetic rats, potentially by modulating the expression of PEPCK and GLUT4

BACKGROUND

Rosmarinic acid (RA) is a natural substance that may be useful for treating diabetes mellitus. The present study investigated the effects of RA on glucose homeostasis and insulin regulation in rats with streptozocin (STZ)-induced type 1 diabetes or high-fat diet (HFD)-induced type 2 diabetes.

METHODS

Glucose homeostasis was determined using oral glucose tolerance tests and postprandial glucose tests, and insulin activity was evaluated using insulin tolerance tests and the homeostatic model assessment for insulin resistance. Additionally, the protein expression levels of PEPCK and GLUT4 were determined using Western blot analysis.

RESULTS

RA administration exerted a marked hypoglycemic effect on STZ-induced diabetic rats and enhanced glucose utilization and insulin sensitivity in HFD-fed diabetic rats. These effects of RA were dose-dependent. Meanwhile, RA administration reversed the STZ- and HFD-induced increase in PEPCK expression in the liver and the STZ- and HFD-induced decrease in GLUT4 expression in skeletal muscle.

CONCLUSION

RA reduces hyperglycemia and ameliorates insulin sensitivity by decreasing PEPCK expression and increasing GLUT4 expression.

Effects of borneol on the pharmacokinetics of 9-nitrocamptothecin encapsulated in PLGA nanoparticles with different size via oral administration

CONTEXT

Although nanocarriers provide promising potential for oral drug delivery, the delivery efficiency remains unsatisfactory and needs to be improved. Size is considered to be the most important characteristic of nanoparticles related to their oral absorption. Borneol has been proved to have the ability to enhance the penetration and transport of many drugs through various physical barriers.

OBJECTIVE

To investigate the effect of the particle size and coadministration of borneol on the pharmacokinetics and bioavailability of entrapped drug in different size poly(lactic-co-glycolic acid) (PLGA) nanoparticles.

MATERIALS AND METHODS

9-Nitrocamptothecin (9-NC)-loaded PLGA nanoparticles with three different range of size (50-100 nm, 100-200 nm, 200-300 nm) were prepared by emulsion solvent-evaporation method. The pharmacokinetic study in rats of these nanoparticles with borneol was carried out.

RESULTS

The experiments showed that the encapsulation drug in nanoparticles with size below 200 nm could improve the oral bioavailability of 9-NC. The small size nanoparticles (50-100 nm) had a better improvement efficacy. As for borneol, it played a significant promotion effect only on the small nanoparticles. Moreover, there was no significant influence on the nanoparticles with size more than 100 nm.

DISCUSSION AND CONCLUSION

The study indicated that both entrapping drug in nanoparticles with the size below 100 nm and coadministrating with borneol could enhance the gastrointestinal absorption of water insoluble drug. The combination of the two strategies provides a potential approach to improve the oral bioavailability of drug.

Synergism of Chinese Herbal Medicine: Illustrated by Danshen Compound

The primary therapeutic effects of Chinese herbal medicine (CHM) are based on the properties of each herb and the strategic combination of herbs in formulae. The herbal formulae are constructed according to Chinese medicine theory: the “Traditional Principles for Constructing Chinese Herbal Medicinal Formulae” and the “Principles of Combining Medicinal Substances.” These principles of formulation detail how and why multiple medicinal herbs with different properties are combined together into a single formula. However, the concept of herbal synergism in CHM still remains a mystery due to lack of scientific data and modern assessment methods. The Compound Danshen Formula (CDF) is a validated formula that has been used to treat a variety of diseases for hundreds of years in China and other countries. The CDF will be employed to illustrate the theory and principle of Chinese herbal medicine formulation. The aim of this review is to describe how Chinese herbal medicinal formulae are constructed according to Chinese medicine theory and to illustrate with scientific evidence how Chinese herbs work synergistically within a formula, thereby supporting Chinese medicine theory and practice.

Review of Scientific Evidence of Medicinal Convoy Plants in Traditional Persian Medicine

One concept used in traditional Persian medicine (TPM) for multidrug therapy is that of the convoy drug (Mobadregh). According to TPM texts, convoy drugs are substances (or drugs), which facilitate the access of drugs or foods to the whole body or to specific organs. This study reviewed some convoy drugs presented in TPM, their biological effects, and their probable interactions with main drugs, considering the increased absorption through inhibition of P-glycoprotein (P-gp) efflux function, bioavailability-enhancing effects, and decreased metabolism of the main drug using electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar in November and December, 2013. Recent studies have proven the beneficial effects of Crocus sativus L. (saffron) and camphor on the heart and brain, the cerebral therapeutic effects of Asarum europaeum (hazelwort), the hepatoprotective effects of Cichorium intybus (chicory), and Apium graveolens (celery) seeds, and the diuretic effects of Cinnamomum zeylanicum (cinnamon), and Cucumis melo (melon) seeds. The effects of vinegar in targeting the liver and brain have also been demonstrated. An evaluation of the results demonstrated that the suggested convoy drugs, including Piper nigrum (black pepper), Piper longum (long pepper), red wine, Camellia sinensis (tea), hazelwort, Mentha longifolia (pennyroyal), Anethum graveolens (dill), Foeniculum vulgare (fennel), cinnamon, and Sassafras albidum (sassafras) can increase the bioavailability of coadministered drugs by inhibition of P-gp or cytochrome P450s (CYP450s) or both of them. This evidence could be a good basis for the use of these agents as convoys in TPM.

The anti-atherosclerotic effect of tanshinol borneol ester using fecal metabolomics based on liquid chromatography-mass spectrometry

Tanshinol borneol ester (DBZ) is a novel experimental compound that consists of two chemical structural units from danshensu and borneol. It exhibits efficacious anti-ischemic and anti-atherosclerosis activities in rats. A fecal metabolomics based on Liquid Chromatography-Mass Spectrometry combined with clinical histopathology and blood lipid estimation was employed to assess the efficacy and the metabolic changes caused by administration of DBZ in atherosclerotic rats. There were the typical pathological features of atherosclerosis and significantly increased levels of TC, TG and LDL-C in the atherosclerotic rat group. Nevertheless, atherosclerotic rats administered both DBZ (at a dose of 40 mg kg(-1)) and simvastatin (at a dose of 20 mg kg(-1)) showed good therapeutic effects. The results of the metabolomics studies showed that 55 differential metabolites such as sebacic acid, enterodiol, nonanedioic acid, dodecanedioic acid, cholic acid, 13(S)-HPODE, deoxycholic acid, some phosphatidylglycerol and phosphatidic acids were found, indicating that abnormal metabolism occurred in the pathways of fatty acid oxidation, linoleic acid metabolism, bile acid biosynthesis and glycerophospholipid metabolism in atherosclerotic rats. Compared to those in the model group, the contents of 41 differential metabolites showed a tendency to recover to a healthy level after DBZ administration. Metabolomics studies suggested that DBZ exhibited good treatment efficacy against atherosclerosis by adjusting disturbed metabolic pathways related to atherosclerosis. This study could provide an experimental basis for DBZ's application to act as a candidate drug with anti-atherosclerosis activity.

Effect of natural borneol on the pharmacokinetics and distribution of nimodipine in mice

The purpose of this study was to investigate the effect of natural borneol (NB) on the pharmacokinetics and distribution of nimodipine in mice. A single dose of nimodipine was administered intravenously (2 mg/kg) to mice pretreated with NB (250 mg/kg) or vehicle. Blood as well as brain, liver, and kidney tissue samples were collected at 5, 10, 20, 40, and 60 min post-dose nimodipine. The concentrations of nimodipine in plasma and tissues were determined by ultra performance liquid chromatography (UPLC) coupled with UV detection, and the pharmacokinetic parameters were calculated based on non-compartmental analysis. NB increased the plasma AUC5-60 min by 26 % compared to the vehicle. In addition, brain concentrations of nimodipine in NB-treated mice were significantly higher than those in control mice with the increased AUC5-60 min by 30 %. In liver and kidney, NB also caused 26 and 47 % increase in AUC5-60 min, respectively. These results implicated that NB may inhibit the metabolism or elimination of nimodipine and enhance its distribution in brain and kidney tissue.

Liquid Chromatography/Quadrupole Time-of-Flight Mass Spectrometry for Identification of In Vitro and In Vivo Metabolites of Bornyl Gallate in Rats

Bornyl gallate (BG) is a potential drug candidate synthesized by the reaction of two natural products, gallic acid and borneol. Previous studies have strongly suggested that BG is worthy of further investigation due to antioxidant, antiatherosclerosis activities, and obvious activity of stimulating intersegmental vessel growth in zebrafish. This work was designed to elucidate the metabolic profile of BG through analyzing its metabolites in vitro and in vivo by a chromatographic separation coupled with a mass spectrometry. The metabolites of BG were characterized from the rat liver microsome incubation solution, as well as rat urine and plasma after oral administration. Chromatographic separation was performed on an Agilent TC-C18 column (250 mm × 4.6 mm, 5  μ m) with gradient elution using methanol and water containing 0.2% (V : V) formic acid as the mobile phase. Metabolites identification involved analyzing the retention behaviors, changes of molecular weights and MS/MS fragment patterns of BG and the metabolites. Five compounds were identified as isomers of hydroxylated BG metabolites in vitro. The major metabolites of BG in rat urine and plasma proved to be BG-O-glucuronide and O-methyl BG-O-glucuronide. The proposed method confirmed to be a reliable and sensitive alternative for characterizing metabolic pathways of BG.

Intestinal absorption and bioavailability of traditional Chinese medicines: a review of recent experimental progress and implication for quality control

Objectives

Experimental studies on the pharmacokinetics of traditional Chinese medicines (TCMs) have achieved great progress in recent years. This review aims to summarize the progress made on intestinal absorption and bioavailability of TCMs, and proposes the application of intestinal absorption assays as new tools for the quality and safety control of these medicines.

Key findings

Since only the absorbed constituents may produce possible therapeutic effect (except those that directly target the digestive tract), intestinal absorption is of utmost importance for the drug action of TCMs, which are usually taken orally. Meanwhile, complicated drug interactions may occur among the multiple ingredients in a herbal mixture. In this regard, the intestinal permeability assays not only provide useful pharmacokinetic data of TCMs, but have potential applications for quality and safety control. Moreover, knockout animals, 2/4/A1 in-vitro cell model and physiologically-based in-silico models based on the online TCM database can be quite useful for the prediction of absorption and bioavailability of TCMs.

Summary

A variety of in-vivo, in-vitro, in-situ and in-silico models for predicting the intestinal absorption and bioavailability can be applied to study the herbal interactions and screen appropriate biomarkers for the quality and safety control of TCMs.

The use of PEGylated liposomes to prolong the circulation lifetime of salvianolic acid B

The clinical application of salvianolic acid B (Sal B), a potential therapeutic agent for cardiovascular diseases isolated from Salvia miltiorrhiza, is greatly restricted by its short half-life and low bioavailability. To improve therapeutic effects and prolong the systemic circulation time of Sal B, liposomes, composed of soybean phosphatidylcholine and cholesterol were prepared by reverse-phase evaporation method. In addition, polyethylene glycol 2000-disteroylphosphoethanolamine (PEG-DSPE 2000) was included to give steric barrier to liposomes. A central composite design was employed to optimize liposomal formulation with high encapsulation efficiency and small particle size. Physicochemical characteristics such as particle size, zeta potential, encapsulation efficiency and in vitro release were investigated. In vivo pharmacokinetic properties of Sal B in beagle dogs and the effect of PEG on the blood circulation time of Sal B-loaded liposomes were also evaluated. An optimized formulation with encapsulation efficiency of 73.68% and mean particle size of 136.6nm were developed. Encapsulation of Sal B into conventional and PEGylated liposomes could prolong the half-life of Sal B by 5.8- and 17.5-fold and enhance the AUC(0-t) of Sal B by 6.7- and 13.3-fold compared with free Sal B, respectively. Therefore, the use of PEGylated liposomes could prolong the circulation time in blood and longevity effect of liposomes on Sal B was increased by PEG.